.\" Copyright (c) 2018 Mariusz Zaborski <oshogbo@FreeBSD.org>
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.Dd November 15, 2021
.Dt LIBCASPER 3
.Os
.Sh NAME
.Nm CREATE_SERVICE
.Nd "casper service declaration macro"
.Sh LIBRARY
.Lb libcasper
.Sh SYNOPSIS
.In sys/nv.h
.In libcasper.h
.In libcasper_service.h
.Bd -literal
typedef int service_limit_func_t(const nvlist_t *, const nvlist_t *);

typedef int service_command_func_t(const char *, const nvlist_t *, nvlist_t *,
    nvlist_t *);

.Ed
.Fn CREATE_SERVICE "name" "limit_func" "command_func" "flags"
.Sh DESCRIPTION
The
.Nm CREATE_SERVICE
macro is used to create a new casper service.
The
.Fa name
is a string containing the service name, which will be used in the
.Xr cap_service_open 3 ,
function to identify it.
.Pp
The
.Fa limit_func
is a function of type
.Li service_limit_func_t
where the first argument of the function contains an
.Xr nvlist 9 ,
old service limits and
the second argument contains the new limits.
If the service was not limited then the old limits will be set to
.Dv NULL .
This function must not allow the extension of service limits.
The
.Fa command_func
is a function of type
.Li service_command_func_t
where the first argument is the name of the command that should be executed.
The first
.Xr nvlist 9
contains the current limits and the second contains an
.Xr nvlist 9
with the current request.
The last argument contains a return value
.Xr nvlist 9
which contains the response from casper.
.Pp
The
.Fa flags
argument defines the limits of the service.
The supported flags are:
.Bl -ohang -offset indent
.It CASPER_SERVICE_STDIO
The casper service has access to the stdio descriptors from the process it was
spawned from.
.It CASPER_SERVICE_FD
The casper service has access to all of the descriptors,
besides the stdio descriptors,
from the process it was spawned from.
.It CASPER_SERVICE_NO_UNIQ_LIMITS
The whole casper communication is using an
.Xr nvlist 9
with the
.Dv NV_FLAG_NO_UNIQUE
flag.
.El
.Sh SEE ALSO
.Xr cap_enter 2 ,
.Xr libcasper 3 ,
.Xr capsicum 4 ,
.Xr nv 9
.Sh HISTORY
The
.Nm libcasper
library first appeared in
.Fx 10.3 .
.Sh AUTHORS
The
.Nm libcasper
library was implemented by
.An Pawel Jakub Dawidek Aq Mt pawel@dawidek.net
under sponsorship from the FreeBSD Foundation.
The
.Nm libcasper
new architecture was implemented by
.An Mariusz Zaborski Aq Mt oshogbo@FreeBSD.org
.
